Estoy tratando de implementar Aes-128-gcm pero cada vez que intento ejecutar el código devuelve "RangeError: Longitud de clave no válida"

 const crypto = require('crypto'); const encryptionKey = crypto.randomBytes(32); const IV = crypto.randomBytes(16); const data = "who let the dogs out"; var encrypt = ((dataValue) => { let cipher = crypto.createCipheriv('aes-128-gcm', encryptionKey, IV); let encrypted = cipher.update(dataValue, 'utf8', 'base64'); encrypted += cipher.final('base64'); return encrypted; }); var decrypt = ((encrypted) => { let decipher = crypto.createDecipheriv('aes-128-gcm', encryptionKey, IV); let decrypted = decipher.update(encrypted, 'base64', 'utf8'); return (decrypted + decipher.final('utf8')); });

¿Qué he hecho mal?